Sunday, May 20th, 2018 AT 2:55 PM
VERNON G GANO JR
- MEMBER
- 2005 NISSAN ALTIMA
- 3.5L
- 6 CYL
- 2WD
- AUTOMATIC
- 140,000 MILES
The AC/heat fan will not turn off?
SPONSORED LINKS
My blower motor will not shut off it just keeps going?
9 Replies
KEN L
- MASTER CERTIFIED MECHANIC
- 48,356 POSTS
The blower motor is staying on yes? This is caused by the blower motor amplifier shorting out. Below is a blower motor wiring diagram so you can see how the system works and where the amplifier is located unplug it to see if the blower motor stops.
Check out the diagrams (below). Please let us know what happens.
Cheers, Ken
Check out the diagrams (below). Please let us know what happens.
Cheers, Ken
Images (Click to make bigger)
SPONSORED LINKS
Was this helpful?
Yes
No
+1
Tuesday, May 22nd, 2018 AT 11:49 AM
VERNON G GANO JR
- MEMBER
- 2 POSTS
I found and replaced it. Works fine now thanks.
Was this helpful?
Yes
No
Wednesday, May 23rd, 2018 AT 6:27 AM
KEN L
- MASTER CERTIFIED MECHANIC
- 48,356 POSTS
Nice work, we are here to help, please use 2CarPros anytime.
Cheers, Ken
Cheers, Ken
Was this helpful?
Yes
No
Wednesday, May 23rd, 2018 AT 10:46 AM
DAVID020585
- MEMBER
- 3 POSTS
- 2005 NISSAN ALTIMA
Got into my car this morning and my fan blower won't cut off. It stays on high. The heating element and A/C work, as well as the circulation.
Was this helpful?
Yes
No
+2
Tuesday, May 25th, 2021 AT 11:20 AM
(Merged)
KASEKENNY
- MECHANIC
- 18,907 POSTS
This could be a could things but most likely it is the blower controller is shorted.
In your vehicle this is called the front air control module. We need to test voltage coming from the highlighted wire when changing speed of the fan and i am sure this will not change. If it does not, then we need to suspect the amplifier is the cause. Basically this changes the resistance of the ground to change the speed of the fan.
I attached below the complete testing and replacement if you need to replace the blower or the amp. Let's run through this testing and go from there.
Here is a guide that will with this type of testing:
https://www.2carpros.com/articles/how-to-check-wiring
Thanks
In your vehicle this is called the front air control module. We need to test voltage coming from the highlighted wire when changing speed of the fan and i am sure this will not change. If it does not, then we need to suspect the amplifier is the cause. Basically this changes the resistance of the ground to change the speed of the fan.
I attached below the complete testing and replacement if you need to replace the blower or the amp. Let's run through this testing and go from there.
Here is a guide that will with this type of testing:
https://www.2carpros.com/articles/how-to-check-wiring
Thanks
Images (Click to make bigger)
SPONSORED LINKS
Was this helpful?
Yes
No
Tuesday, May 25th, 2021 AT 11:20 AM
(Merged)
JHNBOS
- MEMBER
- 1 POST
- 2005 NISSAN ALTIMA
- 103,000 MILES
The air is blowing on high even when the A/C is off and the knob is in any position. What else should I check? I can adjust the vents, and where the air blows from (defrost/floor/combo), but it is constantly on high. I have checked all of the fuses and they all are good. The compressor works, and kicks in fine, and the air blows cold with no smell.
Was this helpful?
Yes
No
+2
Tuesday, May 25th, 2021 AT 11:20 AM
(Merged)
RIVERMIKERAT
- MECHANIC
- 6,110 POSTS
The blower motor is constantly receiving high current. This could be the control module or the fan control switch. Check the blower motor resister for damage or short.
Was this helpful?
Yes
No
+4
Tuesday, May 25th, 2021 AT 11:20 AM
(Merged)
NWALKER1
- MEMBER
- 2 POSTS
- 2005 NISSAN ALTIMA
- 4 CYL
- 2WD
- AUTOMATIC
- 100,000 MILES
I would like to know why the blower won't go off
Was this helpful?
Yes
No
Tuesday, May 25th, 2021 AT 11:20 AM
(Merged)
JACOBANDNICKOLAS
- MECHANIC
- 109,872 POSTS
Hi and thanks for using 2CarPros.com. I have to be honest, I have a feeling the switch itself is bad. What I have seen happen with these is the switch melts down internally allowing current to constantly run. Here is what I suggest. First, you need to access the blower motor unit. Here directions and a picture to help do that.
REMOVAL
Remove the glove box assembly. Refer to "Instrument Lower Cover RH and Glove Box".
Remove the ECM.
Disconnect the blower motor, intake door motor and blower motor resistor connector.
Remove the two bolts and one screw from the blower unit, then remove it.
INSTALLATION
Installation is in the reverse order of removal.
Next, you need to access the motor itself. Here are the directions and a picture for that.
BLOWER MOTOR
Removal and Installation
REMOVAL
Remove the blower unit. Refer to "Removal and Installation"
Release the eight tabs attaching blower motor to blower unit case and then remove it.
INSTALLATION
Installation is in the reverse order of removal.
Once you access the motor, disconnect the wiring to it and you will need to check for power to the motor. Here are directions and a video to help you use a test light.
https://youtu.be/Hlna_kUt7As
https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester
Now that you have the wiring removed, prove the different wires for power using the test light. See if the power stays on at all times regardless of the switch position. If it does, chances are the switch is bad. If the power supply changes location, suspect a short to power.
I have attached a wiring schematic for your review. I hope it helps.
Take care and let me know if you identify the problem.
Joe
REMOVAL
Remove the glove box assembly. Refer to "Instrument Lower Cover RH and Glove Box".
Remove the ECM.
Disconnect the blower motor, intake door motor and blower motor resistor connector.
Remove the two bolts and one screw from the blower unit, then remove it.
INSTALLATION
Installation is in the reverse order of removal.
Next, you need to access the motor itself. Here are the directions and a picture for that.
BLOWER MOTOR
Removal and Installation
REMOVAL
Remove the blower unit. Refer to "Removal and Installation"
Release the eight tabs attaching blower motor to blower unit case and then remove it.
INSTALLATION
Installation is in the reverse order of removal.
Once you access the motor, disconnect the wiring to it and you will need to check for power to the motor. Here are directions and a video to help you use a test light.
https://youtu.be/Hlna_kUt7As
https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester
Now that you have the wiring removed, prove the different wires for power using the test light. See if the power stays on at all times regardless of the switch position. If it does, chances are the switch is bad. If the power supply changes location, suspect a short to power.
I have attached a wiring schematic for your review. I hope it helps.
Take care and let me know if you identify the problem.
Joe
Images (Click to make bigger)
Was this helpful?
Yes
No
+1
Tuesday, May 25th, 2021 AT 11:20 AM
(Merged)
Related Blower Fan Stays On Content
Sponsored links
SPONSORED LINKS
How to Use a Test Light
How to Replace the A/C Blower Motor
How to Find Low Side A/C Service Port
